The present invention relates to a process for preparing a thermoplastic resin composition capable of giving delustered products, and more particularly to a process for preparing a thermoplastic resin composition capable of giving shaped articles having delustered surface by blending (A) a graft-copolymer prepared by adding a nonionic or cationic polyacrylamide coagulant to a rubber-like diene polymer (hereinafter referred to as diene rubber) latex to coagulate a rubber particle, and then reacting coagulated rubber particles with at least one monomer selected from the group consisting of an aromatic vinyl monomer, a vinyl cyanide monomer and a methacrylic acid ester and (B) a polymer prepared from at least one monomer selected from the group consisting of an aromatic vinyl monomer, a vinyl cyanide monomer, an acrylic acid ester and a methacrylic acid ester.
An acrylonitrile/butadiene/styrene copolymer (ABS resin) can give shaped articles having an excellently glossy surface and have an excellent processability. Moreover, it has well-balanced heat resistance and impact resistance, and its cost is not high. Accordingly, the use of the ABS resin has been increased in various fields including parts for electric device, car parts and the like.
Recently, however, so-called delustered ABS resin that the glossiness of the ABS resin itself is controlled has been increasingly demanded for the use of car interior goods or the like, because shaped articles prepared from the delustered resin can give quiet feeling, high-grade feeling and car safety by controlling a reflection of light from a front-panel. Accordingly, there have been proposed various processes for preparing the ABS resin composition capable of giving delustered articles.
That is, there have been carried out, for instance, a process in which shaped articles are delustered by adding inorganic material such as silica or glass beads to an ABS resin composition, a process in which shaped articles having an uneven surface are molded by addition of a third component such as rubber or organic materials to give shaped articles having delustered surface, a mechanical process in which a mold or roll for wrinkling finish is employed, a process in which a paint is coated on a surface of shaped article, and the like.
However, in accordance with any delustering processes by addition of inorganic or organic materials to a resin composition, suitable shaped articles cannot be obtained. That is, in case of the delustering process by addition of the inorganic material, the delustering property of the inorganic material is unsatisfactory, and moreover the impact strength of the shaped article lowers. In case of the delustering process by addition of the organic material, the heat resistance and weatherability of the obtained composition are lower or the processability of the composition is poor unless the obtained shaped article has unsatisfactory delustered surface or unevenly delustered surface. In case of the delustering process by employing the mold or roll for wrinkling finish or the flat paint, the processing cost is high.
An object of the present invention is to provide a process for preparing a thermoplastic resin composition capable of avoiding the above-mentioned conventional problems as well as capable of giving sufficiently delustered shaped articles.
A further object of the present invention is to provide an easy process for preparing a thermoplastic resin composition capable of giving delustered shaped articles.
These and other objects of the present invention will become apparant from the description hereinafter.